Dumbbell



FIG. 1 is a top perspective view of a dumbbell.

FIG. 2 is a left side elevational view of the dumbbell.

FIG. 3 is a right side elevational view of the dumbbell.

FIG. 4 is an end elevational view of the dumbbell, the opposite end being a mirror image thereof.

FIG. 5 is a top plan view of the dumbbell; and,

FIG. 6 is a bottom plan view of the dumbbell.

The broken lines illustrate portions of the dumbbell which form no part of the claimed design. 

The ornamental design for a dumbbell, as shown and described. 